In the operation of various machines in which the ambient atmosphere is very dusty oor contains a substantial amount of other extraneous material, problems arise, particularly in regard to operating the machines in a manner to render them free from obstruction in various ways from said dust and extraneous material. For example, internal combustion engines frequently are water-cooled and the temperature is maintained operative by the use of radiators through which ambient air is drawn by means of suitable fans to reduce the temperature of the cooling water for the engine. Further, if the radiator is fo the type having a multitude of passages therethrough, said passages can be clogged by said dust and extraneous material and thereby greatly decrease the efficiency of the cooling capacity of the radiator, to such extent that the engine wall or can become overheated.
The foregoing situation is particularly prevelant in agricultural equipment in which the same is driven by water-cooled internal combustion engines that employ fin type radiators to maintain the temperature of the cooling water at an operative level. A fan normally is utilized to draw cooling air through the radiator but under circumstances where a substantial amount of dust or extraneous material, such as chaff and the like, is present in the atmosphere, the spaces between the fins and tubes of the radiator are capable of becoming clogged with such material and thereby minimize the cooling capacity and cause overheating of such internal combustion engines.
Efforts to obviate the aforementioned difficulties have been developed heretofore by utilizing rotary screens of different types which are driven at desired speeds and are located adjacent the inlet to the cooling radiator for the engine and various means have been utilized to render such screens free from any appreciable amount of clogging by said dust or extraneous material, such as chaff.
The following patents represent certain of the efforts to remove the dust from such screens:
U.S. Pat. No. 395,801 to Weeks, dated Jan. 8, 1889, shows a dust collector in which a cylindrical screen B around which an endless apron or dust-collecting surface C passes for support thereby. A plurality of balls or other forms of loose bodies N are disposed within the screen and function during the operation thereof to attempt to loosen the dust from the apron as it moves around said screen B.
U.S. Pat. No. 956,862 to Meyer, dated May 3, 1910, shows a vacuum dust remover in which a cylindrical filter screen formed from flannel in which the minute fibers thereof serve to hold the particles of dust away from closer contact with the pores of the filter, and thereby, are intended to insure a free passage of air through the body of the filter.
U.S. Pat. No. 1,124,574 to Zimmer, dated Jan. 12, 1915 and subsequent U.S. Pat. No. 1,176,721 to Zimmer, dated Mar. 21, 1916, show what are stated to be self-cleaning bags for vacuum cleaners in which the bags are stretched between vertically spaced members in which the lower member is supported by vertically extending spring means which are arranged so that slight pulsations transmitted through the conduit from the pump will have a tendency to continuously vibrate the coil springs and thereby agitate the filter surface to tend to induce the material filtered from the air to fall therefrom.
The present invention has been developed to employ means different from those which are disclosed in the aforementioned patents for purposes of loosening and removing any dust or extraneous chaff material and the like from a rotating filter screen associated with the radiator of an internal combustion engine, details of which are set forth below.